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Comparative analysis of transcriptomic responses to sub-lethal levels of six environmentally relevant pesticides in Saccharomyces cerevisiae
No full textThis deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: https://link.springer.com/article/10.1007%2Fs10646-018-1929-1Accidental spills and misuse of pesticides may lead to current and/or legacy environmental contamination and may pose concerns regarding possible risks towards non-target microbes and higher eukaryotes in ecosystems. The present study was aimed at comparing transcriptomic responses to effects of sub-lethal levels of six environmentally relevant pesticide active substances in the Saccharomyces cerevisiae eukaryotic model. The insecticide carbofuran, the fungicide pyrimethanil and the herbicides alachlor, S-metolachlor, diuron and methyl(4-chloro-2-methylphenoxy)acetate were studied. Some are currently used agricultural pesticides, while others are under restricted utilization or banned in Europe and/or North America albeit being used in other geographical locations. In the present work transcriptional profiles representing genome-wide responses in a standardized yeast population upon 2 h of exposure to concentrations of each compound exerting equivalent toxic effects, i.e., inhibition of growth by 20% relative to the untreated control cells, were examined. Hierarchical clustering and Venn analyses of the datasets of differentially expressed genes pointed out transcriptional patterns distinguishable between the six active substances. Functional enrichment analyses allowed predicting mechanisms of pesticide toxicity and response to pesticide stress in the yeast model. In general, variations in transcript numbers of selected genes assessed by Real-Time quantitative reverse transcription polymerase chain reaction confirmed microarray data and correlated well with growth inhibitory effects. A possible biological relevance of mechanistic predictions arising from these comparative transcriptomic analyses is discussed in the context of better understanding potential modes of action and adverse side-effects of pesticides.Fundação para a Ciência e Tecnologia grants:(UID/BIO/04565/2013, PTDC/AMB/64230/2006, SFRH/BD/60933/2009); POR Lisboa 2020 grant: (LISBOA-01-0145-FEDER-007317); FEDER; COMPETE.info:eu-repo/semantics/acceptedVersio
Collective electrical oscillations of a diatom population induced by dark stress
No full textThis deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: https://www.nature.com/articles/s41598-018-23928-9Diatoms are photosynthetic microalgae, a group with a major environmental role on the planet due to the biogeochemical cycling of silica and global fixation of carbon. However, they can evolve into harmful blooms through a resourceful communication mechanism, not yet fully understood. Here, we demonstrate that a population of diatoms under darkness show quasi-periodic electrical oscillations, or intercellular waves. The origin is paracrine signaling, which is a feedback, or survival, mechanism that counteracts changes in the physicochemical environment. The intracellular messenger is related to Ca2+ions since spatiotemporal changes in their concentration match the characteristics of the intercellular waves. Our conclusion is supported by using a Ca2+channel inhibitor. The transport of Ca2+ions through the membrane to the extracellular medium is blocked and the intercellular waves disappear. The translation of microalgae cooperative signaling paves the way for early detection and prevention of harmful blooms and an extensive range of stress-induced alterations in the aquatic ecosystem.Fundação para a Ciência e Tecnologia grants: (SFRH/BPD/91518/2012, UID/Multi/04326/2013); project SNMB - INOV; Operational Program (OP) Mar 2020; Portugal 2020; European Union: [European Structural Funds and Investment Funds (FEEI) and European Maritime and Fisheries Fund (EMFF)].info:eu-repo/semantics/publishedVersio
Microbial Diversity and Toxin Risk in Tropical Freshwater Reservoirs of Cape Verde
Full text linkThis deposit is composed by the main article plus the supplementary materials of the publication.The Cape Verde islands are part of the African Sahelian arid belt that possesses an erratic rain pattern prompting the need for water reservoirs, which are now critical for the country’s sustainability. Worldwide, freshwater cyanobacterial blooms are increasing in frequency due to global climate change and the eutrophication of water bodies, particularly in reservoirs. To date, there have been no risk assessments of cyanobacterial toxin production in these man-made structures. We evaluated this potential risk using 16S rRNA gene amplicon sequencing and full metagenome sequencing in freshwater reservoirs of Cape Verde. Our analysis revealed the presence of several potentially toxic cyanobacterial genera in all sampled reservoirs. Faveta potentially toxic and bloom-forming Microcystis sp., dominated our samples, while a Cryptomonas green algae and Gammaproteobacteria dominated Saquinho and Poilão reservoirs. We reconstructed and assembled the Microcystis genome, extracted from the metagenome of bulk DNA from Faveta water. Phylogenetic analysis of Microcystis cf. aeruginosa CV01’s genome revealed its close relationship with other Microcystis genomes, as well as clustering with other continental African strains, suggesting geographical coherency. In addition, it revealed several clusters of known toxin-producing genes. This survey reinforces the need to better understand the country’s microbial ecology as a whole of water reservoirs on the rise.Portuguese Science and Technology Foundation grants: (PTDC/MAR-BIO/4132/2014, SFRH/BD/113752/2015, SFRH/BPD/91518/2012).info:eu-repo/semantics/publishedVersio
Regulatory landscape of the Hox transcriptome
Full text linkPrecise regulation of Hox gene activity is essential to achieve proper control of animal embryonic development and to avoid generation of a variety of malignancies. This is a multilayered process, including complex polycistronic transcription, RNA processing, microRNA repression, long noncoding RNA regulation and sequence-specific translational control, acting together to achieve robust quantitative and qualitative Hox protein output. For many such mechanisms, the Hox cluster gene network has turned out to serve as a paradigmatic model for their study. In this review, we discuss current knowledge of how the different layers of post-transcriptional regulation and the production of a variety of noncoding RNA species control Hox output, and how this shapes formation of developmental systems that are reproducibly patterned by complex Hox networks.Fundação para a Ciência e a Tecnologia grants: ( PTDC/BEX-BID/0899/2014, SFRH/BD/51876/2012); Santa Casa da Misericordia de Lisboa grant: (SCML-MC-60-2014);info:eu-repo/semantics/publishedVersio
Ferritin H Deficiency in Myeloid Compartments Dysregulates Host Energy Metabolism and Increases Susceptibility to Mycobacterium tuberculosis Infection
No full textThis deposit is composed by the main article plus the supplementary materials of the publication.This deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: https://www.frontiersin.org/articles/10.3389/fimmu.2018.00860/fullIron is an essential factor for the growth and virulence of Mycobacterium tuberculosis (Mtb). However, little is known about the mechanisms by which the host controls iron availability during infection. Since ferritin heavy chain (FtH) is a major intracellular source of reserve iron in the host, we hypothesized that the lack of FtH would cause dysregulated iron homeostasis to exacerbate TB disease. Therefore, we used knockout mice lacking FtH in myeloid-derived cell populations to study Mtb disease progression. We found that FtH plays a critical role in protecting mice against Mtb, as evidenced by increased organ burden, extrapulmonary dissemination, and decreased survival in Fth−/− mice. Flow cytometry analysis showed that reduced levels of FtH contribute to an excessive inflammatory response to exacerbate disease. Extracellular flux analysis showed that FtH is essential for maintaining bioenergetic homeostasis through oxidative phosphorylation. In support of these findings, RNAseq and mass spectrometry analyses demonstrated an essential role for FtH in mitochondrial function and maintenance of central intermediary metabolism in vivo. Further, we show that FtH deficiency leads to iron dysregulation through the hepcidin–ferroportin axis during infection. To assess the clinical significance of our animal studies, we performed a clinicopathological analysis of iron distribution within human TB lung tissue and showed that Mtb severely disrupts iron homeostasis in distinct microanatomic locations of the human lung. We identified hemorrhage as a major source of metabolically inert iron deposition. Importantly, we observed increased iron levels in human TB lung tissue compared to healthy tissue. Overall, these findings advance our understanding of the link between iron-dependent energy metabolism and immunity and provide new insight into iron distribution within the spectrum of human pulmonary TB. These metabolic mechanisms could serve as the foundation for novel host-directed strategies.This work was supported by NIH grants R01AI111940, R21AI127182, a Bill and Melinda Gates Foundation Award (OPP1130017) (to AJCS), DK59600 and DK079337 (to AA) and pilot funds from the UAB Centers for AIDS Research and Free Radical Biology, and UAB School of Medicine Infectious Diseases and Global Health and Vaccines Initiative to AJCS. The research was also co-funded by the South African Medical Research Council to AJCS. This publication is also based on worksupported by a grant from the U.S. Department of Agriculture. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the U.S. Department of Agriculture. Support by Fundação para a Ciência e Tecnologia grants PTDC/SAU-TOX/116627/2010, HMSP-ICT/0022/2010,
European Community seventh Framework Grant ERC-2011-AdG 294709-DAMAGE CONTROL (to MPS).info:eu-repo/semantics/publishedVersio
Logical modelling uncovers developmental constraints for primary sex determination of chicken gonads
No full textThis deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: http://rsif.royalsocietypublishing.org/content/15/142/20180165This deposit is composed by the main article. The supplementary materials can be accessed through the following link: https://figshare.com/collections/Supplementary_material_from_Logical_modelling_uncovers_developmental_constraints_for_primary_sex_determination_of_chicken_gonads_/4094246In the chicken, sex determination relies on a ZZ (male)/ZW (female) chromosomal system, but underlying mechanisms are still not fully understood. The Z-dosage and the dominant W-chromosome hypotheses have been proposed to underlie primary sex determination. We present a modelling approach, which assembles the current knowledge and permits exploration of the regulation of this process in chickens. Relying on published experimental data, we assembled a gene network, which led to a logical model that integrates both the Z-dosage and dominant W hypotheses. This model showed that the sexual fate of chicken gonads results from the resolution of the mutual inhibition between DMRT1 and FOXL2, where the initial amount of DMRT1 product determines the development of the gonads. In this respect, at the initiation step, a W-factor would function as a secondary device, by reducing the amount of DMRT1 in ZW gonads when the sexual fate of the gonad is settled, that is when the SOX9 functional level is established. Developmental constraints that are instrumental in this resolution were identified. These constraints establish qualitative restrictions regarding the relative transcription rates of the genes DMRT1, FOXL2 and HEMGN. Our model further clarified the role of OESTROGEN in maintaining FOXL2 function during ovary development.L.S. received no financial support for this work. C.C. acknowledges the support of the Calouste Gulbenkian Foundation.info:eu-repo/semantics/publishedVersio
Author Correction: Genome-wide analysis of multi- and extensively drug-resistant Mycobacterium tuberculosis
No full textThis deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: https://www.nature.com/articles/s41588-018-0074-3This publication hasn't any creative commons license associated.This deposit is composed simultaneously by the original published article and also by the "correction" for the published article (erratum). The link for the original article: https://www.nature.com/articles/s41588-017-0029-0#Ack1This deposit is composed by the main article plus the supplementary materials of the publication.In the version of this article initially published, the URL listed for TubercuList was incorrect. The correct URL is https://mycobrowser.epfl.ch/. The error has been corrected in the HTML and PDF versions of the article.To characterize the genetic determinants of resistance to antituberculosis drugs, we performed a genome-wide association study (GWAS) of 6,465 Mycobacterium tuberculosis clinical isolates from more than 30 countries. A GWAS approach within a mixed-regression framework was followed by a phylogenetics-based test for independent mutations. In addition to mutations in established and recently described resistance-associated genes, novel mutations were discovered for resistance to cycloserine, ethionamide and para-aminosalicylic acid. The capacity to detect mutations associated with resistance to ethionamide, pyrazinamide, capreomycin, cycloserine and para-aminosalicylic acid was enhanced by inclusion of insertions and deletions. Odds ratios for mutations within candidate genes were found to reflect levels of resistance. New epistatic relationships between candidate drug-resistance-associated genes were identified. Findings also suggest the involvement of efflux pumps (drrA and Rv2688c) in the emergence of resistance. This study will inform the design of new diagnostic tests and expedite the investigation of resistance and compensatory epistatic mechanisms.The project was supported by the KAUST faculty baseline research fund (BAS/1/1020-01-01) to A.P. The authors wish to thank members of the KAUST Bioscience Core laboratory who sequenced samples. We thank the Wellcome Trust Sanger Institute core and pathogen sequencing and informatics teams who were involved in the Malawi and Uganda studies. The work was funded in part by the Wellcome Trust (grant numbers WT096249/Z/11/B, WT088559MA, WT081814/Z/06/Z and WT098051) and the Wellcome Trust–Burroughs Wellcome Fund Infectious Diseases Initiative grant (number 063410/ABC/00/Z). F.C. was the recipient of a Bloomsbury College PhD Studentship and was supported by the Wellcome Trust (201344/Z/16/Z); J. Perdigão received a Fundação para a Ciência e a Tecnologia (Portugal) postdoctoral fellowship fund (SFRH/BPD/95406/2013). The Calouste Gulbenkian Foundation, the Institute Gulbenkian in Lisbon and the European Society of Clinical Microbiology and Infectious Diseases supported the research of C.P., J. Perdigão, I.P. and M.V. J. Phelan is funded by a BBSRC PhD studentship. T.G.C. is funded by the Medical Research Council UK (grant numbers MR/K000551/1, MR/M01360X/1, MR/N010469/1 and MC_PC_15103). N.F. is funded by the Medical Research Council UK (grant number MR/K020420/1). T.M. is supported by the Ministry of Health, Labor and Welfare of Japan (H21-Shinkou-Ippan-008 and H24-Shinkou-Ippan-010).info:eu-repo/semantics/publishedVersio
iTAP, a novel iRhom interactor, controls TNF secretion by policing the stability of iRhom/TACE
Full text linkThe apical inflammatory cytokine TNF regulates numerous important biological processes including inflammation and cell death, and drives inflammatory diseases. TNF secretion requires TACE (also called ADAM17), which cleaves TNF from its transmembrane tether. The trafficking of TACE to the cell surface, and stimulation of its proteolytic activity, depends on membrane proteins, called iRhoms. To delineate how the TNF/TACE/iRhom axis is regulated, we performed an immunoprecipitation/mass spectrometry screen to identify iRhom-binding proteins. This identified a novel protein, that we name iTAP (iRhom Tail-Associated Protein) that binds to iRhoms, enhancing the cell surface stability of iRhoms and TACE, preventing their degradation in lysosomes. Depleting iTAP in primary human macrophages profoundly impaired TNF production and tissues from iTAP KO mice exhibit a pronounced depletion in active TACE levels. Our work identifies iTAP as a physiological regulator of TNF signalling and a novel target for the control of inflammation.info:eu-repo/semantics/publishedVersio
Within host selection for faster replicating bacterial symbionts
Full text linkThis deposit is composed by the main article plus the supplementary materials of the publication.The supplementary materials are present in the publisher's page in the following link: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0191530#sec010Wolbachia is a widespread, intracellular symbiont of arthropods, able to induce reproductive distortions and antiviral protection in insects. Wolbachia can also be pathogenic, as is the case with wMelPop, a virulent variant of the endosymbiont of Drosophila melanogaster. An extensive genomic amplification of the 20kb region encompassing eight Wolbachia genes, called Octomom, is responsible for wMelPop virulence. The Octomom copy number in wMelPop can be highly variable between individual D. melanogaster flies, even when comparing siblings arising from a single female. Moreover, Octomom copy number can change rapidly between generations. These data suggest an intra-host variability in Octomom copy number between Wolbachia cells. Since wMelPop Wolbachia with different Octomom copy numbers grow at different rates, we hypothesized that selection could act on this intra-host variability. Here we tested if total Octomom copy number changes during the lifespan of individual Drosophila hosts, revealing selection for different Wolbachia populations. We performed a time course analysis of Octomom amplification in flies whose mothers were controlled for Octomom copy number. We show that despite the Octomom copy number being relatively stable it increases slightly throughout D. melanogaster adult life. This indicates that there is selection acting on the intra-host variation in the Octomom copy number over the lifespan of individual hosts. This within host selection for faster replicating bacterial symbionts may be in conflict with between host selection against highly pathogenic Wolbachia.Fundação para a Ciência e Tecnologia (www.fct.pt) grant PTDC/BEX-GMG/3128/2014; EMBO Long Term Fellowship: (EMBO ALTF 1497-2015); Marie Curie Actions; European Commission grants: (LTFCOFUND2013, GA-2013-609409).info:eu-repo/semantics/publishedVersio
The fitness landscape of the codon space across environments
Full text linkThe deposited article version is the Epub Ahead of Print version of the article, posted online 22 August 2018, provided by Biorxiv. It hasn´t been submitted to peer-review.This deposit is composed by the main article. The supplementary materials can be accessed through the following link: https://www.biorxiv.org/content/early/2018/06/27/252395.figures-onlyFitness landscapes map the relationship between genotypes and fitness. However, most fitness landscape studies ignore the genetic architecture imposed by the codon table and thereby neglect the potential role of synonymous mutations. To quantify the fitness effects of synonymous mutations and their potential impact on adaptation on a fitness landscape, we use a new software based on Bayesian Monte Carlo Markov Chain methods and re-estimate selection coefficients of all possible codon mutations across 9 amino acid positions in Saccharomyces cerevisiae Hsp90 across 6 environments. We quantify the distribution of fitness effects of synonymous mutations and show that it is dominated by many mutations of small or no effect and few mutations of larger effect. We then compare the shape of the codon fitness landscape across amino acid positions and environments, and quantify how the consideration of synonymous fitness effects changes the evolutionary dynamics on these fitness landscapes. Together these results highlight a possible role of synonymous mutations in adaptation and indicate the potential mis-inference when they are neglected in fitness landscape studies.This work was supported by Fundação Calouste Gulbenkian and an ERC Starting Grant to JDJ. I. Fragata was supported by a postdoctoral fellowship from FCT (Fundação para a Ciência e a Tecnologia) within the project JPIAMR/0001/2016.info:eu-repo/semantics/acceptedVersio